The present invention relates to agricultural cultivating tools and, more particularly, to a shank attachment device adaptable for holding either a ripper shank or a finishing tool.
Shank attachment assemblies are available for a variety of single purpose, ground-working tools. One type of ground-working tool that is occasionally utilized for deep tillage of the soil is a ripper shank. Because a ripper shank digs deeply into the soil, several problems arise when such a shank is used. The deep furrowing ripper shank encounters much resistance and must, therefore, be securely mounted to a tool bar. Also, a ripper shank's deep location in the soil increases the likelihood that it will come in contact with a sizable rock, root or other obstruction. Therefore, an attachment for mounting the ripper shank to the tool bar should securely attach the ripper shank thereto but also include a device for allowing the shank to deflect when contacting obstacles in the soil so that the shank does not bend or break. Furthermore, because a ripper shank forms a deep furrow in the soil, ground cultivated with an implement equipped with ripper shanks is often too uneven for immediate crop planting. Therefore, a second pass must be made over the ground with finishing tools to level the ground surface.
Several types of ripper shanks are available that dig deeply into the soil and are mounted on a tool bar by shank attachment devices. Such devices may include either a spring-type trip system or shear pins that fail when the attached shank is placed under severe stress by obstacles in its path.
However, the shank attachment devices utilized with such shanks are often complex. Although such devices may include apparatus for adjusting the depth or position of the attached ripper shank, they are not shaped or otherwise equipped to be readily adaptable for mounting and securely holding ground-working tools other than ripper shanks. Because deep tillage with ripper shanks is an occasionally performed cultivating activity, implements mounted with ripper shanks often sit idle and a second implement must be utilized to level the ground after it is worked with ripper shanks.